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Note 2 - Investments - Schedule of Contractual Maturities (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Available-for-Sale, Amortized Cost | $ 252,272 | $ 328,695
Total securities available-for-sale, fair value | 228,199 | 292,933
Total securities held-to-maturity, amortized cost | 8,500 | 8,500
Total securities held-to-maturity, fair value | 7,983 | 7,666
Total securities, amortized cost | 260,772 | 337,195
Total securities, fair value | 236,182 | 300,599
US Government Agencies Debt Securities [Member] |  |
Due within one year, amortized cost | 0 | 922
Due within one year, fair value | 0 | 914
Due after one year through five years, amortized cost | 4,958 | 3,947
Due after one year through five years, fair value | 4,663 | 3,544
Due after five years through ten years, amortized cost | 10,974 | 11,972
Due after five years through ten years, fair value | 9,470 | 10,139
Due after ten years, amortized cost | 4,310 | 4,310
Due after ten years, fair value | 3,549 | 3,421
Subtotal, amortized cost | 20,242 | 21,151
Subtotal, fair value | 17,682 | 18,018
Available-for-Sale, Amortized Cost | 20,242 | 21,151
Total securities available-for-sale, fair value | 17,682 | 18,018
Corporate Debt Securities [Member] |  |
Due within one year, amortized cost | 0 | 1,000
Due within one year, fair value | 0 | 1,004
Due after one year through five years, amortized cost | 10,000 | 6,000
Due after one year through five years, fair value | 10,004 | 6,609
Due after five years through ten years, amortized cost | 4,000 | 4,000
Due after five years through ten years, fair value | 3,944 | 3,839
Due after ten years, amortized cost | 2,000 | 2,000
Due after ten years, fair value | 1,456 | 1,420
Subtotal, amortized cost | 16,000 | 13,000
Subtotal, fair value | 15,404 | 12,872
Available-for-Sale, Amortized Cost | 16,000 | 13,000
Total securities available-for-sale, fair value | 15,404 | 12,872
Due after five years through ten years, amortized cost, held to maturity | 8,500 | 8,500
Due after five years through ten years, fair value, held to maturity | 7,983 | 7,666
Municipal Bonds [Member] |  |
Due within one year, amortized cost | 0 | 1,013
Due within one year, fair value | 0 | 1,003
Due after one year through five years, amortized cost | 74 | 757
Due after one year through five years, fair value | 74 | 751
Due after five years through ten years, amortized cost | 6,295 | 7,603
Due after five years through ten years, fair value | 5,991 | 7,101
Due after ten years, amortized cost | 76,691 | 129,430
Due after ten years, fair value | 66,261 | 110,592
Subtotal, amortized cost | 83,060 | 138,803
Subtotal, fair value | 72,326 | 119,447
Available-for-Sale, Amortized Cost | 83,060 | 138,803
Total securities available-for-sale, fair value | 72,326 | 119,447
Collateralized Mortgage-Backed Securities [Member] |  |
Without single maturity date, amortized cost | 120,136 | 112,855
Without single maturity date, fair value | 110,919 | 101,248
Available-for-Sale, Amortized Cost | 120,136 | 112,855
Total securities available-for-sale, fair value | 110,919 | 101,248
Collateralized Mortgage-Backed Securities [Member] | Federal National Mortgage Association (FNMA) [Member] |  |
Without single maturity date, amortized cost | 82,062 | 76,369
Without single maturity date, fair value | 73,923 | 66,275
Collateralized Mortgage-Backed Securities [Member] | Federal Home Loan Mortgage Corporation (FHLMC) [Member] |  |
Without single maturity date, amortized cost | 27,525 | 32,311
Without single maturity date, fair value | 26,911 | 31,376
Collateralized Mortgage-Backed Securities [Member] | Government National Mortgage Association (GNMA) [Member] |  |
Without single maturity date, amortized cost | 10,549 | 4,175
Without single maturity date, fair value | 10,085 | 3,597
U.S. Small Business Administration Securities [Member] |  |
Due within one year, amortized cost | 203 | 198
Due within one year, fair value | 200 | 196
Due after one year through five years, amortized cost | 1,073 | 1,860
Due after one year through five years, fair value | 1,046 | 1,824
Due after five years through ten years, amortized cost | 2,868 | 21,420
Due after five years through ten years, fair value | 2,679 | 20,929
Due after ten years, amortized cost | 8,690 | 19,408
Due after ten years, fair value | 7,943 | 18,399
Subtotal, amortized cost | 12,834 | 42,886
Subtotal, fair value | 11,868 | 41,348
Available-for-Sale, Amortized Cost | 12,834 | 42,886
Total securities available-for-sale, fair value | $ 11,868 | $ 41,348

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